A word doesn’t have to be new to get my attention. Today, I am appreciating the word for its own sake and the way it’s been used, observing the word in its natural habitat (in this case, the prose of Patrick O’Brian).

The sky was still grey and it was impossible to say whether it was clear or covered with very high cloud; but the sea itself already had a nacreous light that belonged more to the day than the darkness, and this light was reflected in the great convexities of the topsails, giving them the lustre of grey pearls. (Master and Commander, Chapter 3)

The estimable Molly Gloss recently used Patrick O’Brian’s prose as an exemplar in a craft talk about using long sentences as well as short. Her example, from Desolation Island, showed that his writing was well structured, clear and served the story and its emotional heft. Here we see that clarity; it’s designed for as much transparency as possible. There is a word here that I daresay most readers aren’t familiar with, but the (very long) sentence works around that.

Our rare bird is, of course, nacreous. French-speakers may have an unfair advantage in puzzling out its meaning: nacre is French for mother of pearl (and apparently is the specialized term for the substance in English). Thus something nacreous has the properties of mother of pearl, such as iridescence.

So while O’Brian has used a word he knew to be slightly obscure, he has nested it into a context that allows the reader to approximate its meaning and carry on with the story. It is evidently a quality of light, and from its reflection on the sails he gives us the essential element, its pearlescence. This technique, adding a few expansive phrases and context clues around an uncommon word, is one O’Brian uses elsewhere to allow us to understand nautical terminology. It is part of his genius that in the heat of battle we don’t have to turn aside for a dictionary.